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Finding the Fourth Proportional to 830.80, 1,246.20 and 790.30

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Solution

The fourth proportional to 830.80, 1,246.20 and 790.30 is: 1,185.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.80 : 1,246.20 = 790.30 : x
  2. Step 2: Convert to fraction form
    830.80/1,246.20 = 790.30/x
  3. Step 3: Cross multiply
    830.80x = 1,246.20 × 790.30
  4. Step 4: Simplify right side
    830.80x = 984,871.86
  5. Step 5: Solve for x
    x = 984,871.86/830.80
  6. Step 6: Final answer
    x = 1,185.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.